In a bid to ease the task of writing row and index information to a given page I set out on a major mission (major due to the number of classes that would need modification) to revised the use of explicit member fields and change these into objects that can not only serialise themselves to and from a suitable backing store but also support the concept of being locked.
Locked fields support both read and write of their associated values whereas unlocked fields perform a dummy read of existing data instead of the corresponding write. This makes it easier to update a buffer when extent information of a distribution page changes without causing all distribution page extent changes to require an exclusive object lock - this alone will speed concurrent updates but will need further coordination plus additional LogEntry derived classes to deal with the information actually written in the event of a rollback operation.
As one can imagine with over 100 classes and almost one thousand fields and properties to update this was an erronous task to undertake...
The net result was a true simplification in the implementation of Page object persistence and as an added bonus the persistence of both table and index key information has become so simple I ended up removing classes - that is always a great feeling!
So after a good 50 hours of near continuous programming I have finally got the codebase back to a situation where it builds! It took another 12 hours to fix the variety of bugs and race-condition related problems before the creation of a database is actually working without problem!
No time to rest and relax - I also modified the LogEntry classes to incorporate the same mechanism for reading and writing themselves.
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